In an initial stage in which an electric automobile which travels with power charged in a battery is put on the market, the distance over which the electric automobile can travel when fully charged is short and the number of charging stations where the electric automobile can be charged is small, and consequently the driver is anxious about long distance drive. To cope with this, a technique for giving a sense of security to the driver by making a decision whether battery charging at a driver's destination is possible and displaying charging stations in the vicinity of a retrieved driver's destination or in the vicinity of routes to the driver's destination when the charging at the driver's destination is judged to be impossible is disclosed in patent literature 1 and patent literature 2.